<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>id选择器</title>
</head>

<body>

    <style>
        #para1 {
            text-align: center;
            color: red;
        }
    </style>


    <p id="para1">Hello World!</p>
    <p>本段不受样式的影响。</p>


</body>

</html>